1. Field of the Invention
The present invention relates to plant monitoring equipment, and in particular to systems and methods for determining the condition of a plant with a portable processing device and a central processing system.
2. Description of Related Art
Current techniques for operating and maintaining facilities utilize one or more methodologies: xe2x80x9cBreakdownxe2x80x9d maintenance, or run-to-failure maintenance, is event based and awaits a failure before making repairs. xe2x80x9cPreventivexe2x80x9d maintenance is time based, with repairs or replacements being made on a scheduled basis. xe2x80x9cProactivexe2x80x9d maintenance requires that the root-cause-of-failure-modes be understood and eliminated to prevent failure modes from occurring. xe2x80x9cReliability centeredxe2x80x9d maintenance assigns a risk value to each piece of equipment and sub-component so that maintenance and monitoring can be tailored to reduce risks to acceptable levels.
xe2x80x9cCondition basedxe2x80x9d maintenance (also referred to as predictive maintenance or just-in-time maintenance) waits for an identified need for maintenance before doing that work. This type of maintenance is based on the concept that measurement of the equipment""s condition will indicate the need for repair activity. This technique can be combined with other techniques to achieve xe2x80x9cstrategy assessmentxe2x80x9d maintenance, which requires a theoretical analysis of estimates, assumptions and methods of measurement to provide the most effective mix of breakdown, preventive, predictive and proactive maintenance and methodologies.
In U.S. Pat. No. 4,612,620 hand-held device 10 (FIG. 1) connects to a vibration transducer 18. An operator can take measurements using the transducer, based upon promptings from a test sequence stored in the hand-held device 10. The operator can record qualitative observations by entering code numbers corresponding to predetermined conditions. Afterward, device 10 is taken to a central processor where these test results are uploaded and where a new set of test procedures are downloaded. This reference takes very limited data, does not have an efficient way for quickly identifying the measurement site, and is not generally set up for condition based monitoring of an entire plant.
In U.S. Pat. No. 4,835,372 a number of remote units having bar code scanners are connected in a network to a central computer in a hospital. These remote units may in some cases be hand-held devices connected to the network by an R. F. link. Bar codes are placed on a patient""s bracelet and on a badge carried by nurses and other hospital personnel. Bar code labels are printed for patient""s specimens, special drugs etc. By scanning bar codes on the patient""s bracelet, the nurse""s badge, and on the drugs being administered, these central computer can keep track of the drugs being administered. The central computer can also send a signal to the remote units to notify a nurse of the need to administer a scheduled or overdue drug. The remote units can also have sensor inputs for monitoring blood pressure, temperature, respiration, etc. Alternatively, an operator can type this data into the remote unit instead. This system is not involved with condition based monitoring of a plant.
In U.S. Pat. No. 5,541,840 a hand-held unit 10 can either operate with, or operate independently of, master unit 14 at an automobile repair facility. Hand-held unit 10 can also travel and record test data, while an automobile is taken for a test drive. Thereafter, the hand-held unit 10 can be disconnected from the automobile and connected to master unit 14 for diagnosis. Also, master unit 14 can download test procedures to hand-held unit 10. Again, the system takes very limited data, is unconcerned with identifying various inspection sites, and is not adapted for condition based monitoring.
See U.S. Pat. No. 5,808,903 for a sound card in a PCMCIA slot of a portable computer that collects vibration data from an accelerometer and performs a fast Fourier transform on the collected data. See U.S. Pat. No. 5,557,549 for an expert system for diagnosing maintenance problems. See also U.S. Pat. No. 4,537,067.
Accordingly, there is a need for an improved system and method for monitoring conditions at a plant and efficiently presenting information that would be useful for maintenance purposes.
In accordance with the illustrative embodiments demonstrating features and advantages of the present invention, there is provided a system for determining the condition of a plant, its equipment and facilities, at a plurality of inspection sites identified by a plurality of separate, machine-readable, identification codes. The system has at least one portable processing device with an inspection transducer adapted for sensing and storing in the processing device at least one measured characteristic of the plant equipment. The portable processing device is operable to read at least a selected one of the identification codes associated with the plant equipment. Also included is a central processing system adapted to communicate with and upload from the portable processing device at least the one measured characteristic and at least the selected one of the identification codes. The central processing means is operable in response to at least the one measured characteristic and at least the selected one of the identification codes to produce a condition signal signifying the condition of some aspect of the plant, in response to at least the one measured characteristic and at least the selected one of the identification codes.
In accordance with another aspect of the invention a method is provided that employs a central processing system and at least one portable processing device with an inspection transducer for determining the condition of a plant at a plurality of inspection sites identified by a plurality of separate, machine-readable, identification codes. The method includes the step of sensing and storing in the processing device at least one measured characteristic of the plant by using the inspection transducer. Another step is reading with the portable processing device at least a selected one of the identification codes associated with the inspection sites. The method also includes the step of communicating with and uploading from the portable processing device at least the one measured characteristic and at least the selected one of the identification codes using the central processing system. Also included is the step of producing with the central processing system a condition signal signifying the condition of some aspect of the plant, in response to at least the one measured characteristic and at least the selected one of the identification codes.
Systems and methods according to the principles of the present invention offer a highly cost-effective and unique program for the operation and maintenance of various buildings and grounds facilities. Several current or state-of-the-art technologies may be used in unique ways to achieve greater economies from the operations and maintenance labor and materials resources, while providing a more effective method of tracking the facilities condition. The resulting improved utilization of resources is preferably combined with the continuous, automated tracking of the facilities condition, and can integrate several technologies to provide a continuous, single loop feedback control system for the operation and maintenance of a facility.
The preferred system utilizes the technologies of condition based maintenance, such as, but not limited to, measuring vibration, ultrasound, infrared, ferrography wear particle analysis, etc. While conventional condition based maintenance concentrates primarily on monitoring the conditions of equipment, the preferred system will utilize technology to monitor, take corrective action and update the condition of the entire facility; including equipment, architectural features, finishes, furniture, housekeeping cleanliness, structural features, walls, roofs, grounds, roads, parking lots, sidewalks and curbs. Unlike the condition based maintenance technologies mentioned, the preferred system also collects non-equipment data utilizing a hand-held computer with bar code scanner. Data can be continuously collected into a preferred database program regarding the condition of the entire facility and then compared to a standard. Whenever the program detects a substandard condition, preferably a corrective work order is automatically generated. In the preferred embodiment, the condition of the area being monitored is continuously updated by the program.
The preferred system and methods can reduce maintenance labor required to maintain a facility by limiting the labor force to pre-identified work only. Also, the staff labor required to maintain a facility can be reduced preferably by automating data collection. This continuous collection of facilities maintenance and condition data will increase knowledge of the condition of the facilities. Management effectiveness is increased through the reduction and presentation of facilities maintenance and condition data in a preferred, concise, graphical format. Also, this system and method can provide feedback information on an independent audit basis; that is, the data can be collected independently from the maintenance repair function. This independence fosters highly specialized skills that are more able to adapt to the latest technologies.